knockout observable array not updating after ajax addition

Question

I have an observable array of a complex object. The initial load is fine, and all the expected data looks fine. Now I am working on POSTing new items to that array. NOTE: The observable array is being loaded via ASP.NET ajax web api call.

posting a new item works fine as far as saving it to the database, but my DOM is not getting updated with the new item and I don't know what I am missing.

Here is the entire ViewModel

    function ClientList() {
    //data
    var self = this;
    self.initialized = ko.observable(false);
    self.clients = ko.observableArray();
    self.userId = ko.observable("");
    self.name = ko.observable("");
    self.logo = ko.observable("");
    self.projects = ko.observableArray();
    self.clientAddress = ko.observableArray();


    self.addClient = function () {
        var client = {
            UserId: self.userId,
            Name: self.name,
            Logo: self.logo,
        }
        client = ko.toJSON(client);
        lucidServer.addClient(client);
        self.clients.push(client);
    }.bind(self);

    (function () {
        $.ajax({
            url: lucidServer.getClients(1),
            success: function (data) {
                ko.mapping.fromJS(data, {}, self.clients);
                self.initialized(true);
            }
        });
    })();
};

function IncompleteStoriesList() {
    //data
    var self = this;
    self.initialized = ko.observable(false);
    self.stories = ko.observableArray();
    (function () {
        $.ajax({
            url: lucidServer.getIncompleteStory(1),
            success: function (data) {
                ko.mapping.fromJS(data, {}, self.stories);
                self.initialized(true);
            }
        });
    })();
};


function ViewModel() {
    var self = this;
    self.clientList = new ClientList();
    self.storyList = new IncompleteStoriesList();
}

ko.applyBindings(new ViewModel());

Here is the particular snippet where I am doing the POST (within the ClientList() function).

self.addClient = function () {
        self.client = {
        UserId: self.userId(),
        Name: self.name(),
        Logo: self.logo(),
        }
    //make client object to send to server
    var client = ko.toJSON(self.client);
    lucidServer.addClient(client);
    //push the self.client to the observablearray of clients
    self.clients.push(self.client);
}.bind(self);

I verified it is JSON that is sitting inside the client variable, and no error messages are getting thrown, so I am confused. After I add an item and refresh the entire page, it will show up in the list.

EDIT: here is the html associated:

<form data-bind="submit: clientList.addClient">
    <div>
        <label>userId</label>
        <input type="text" data-bind="value: clientList.userId" />
    </div>
    <div>
        <label>name</label>
        <input type="text" data-bind="value: clientList.name" />
    </div>
    <div>
        <label>logo</label>
        <input type="text" data-bind="value: clientList.logo" />
    </div>
    <button type="submit">Add</button>

    </form>

    <!-- ko ifnot: clientList.initialized -->
    <span>Loading...</span>
    <!-- /ko -->
    <ul data-bind="template:{name: 'clientList', foreach:clientList.clients}">
    </ul>

And the external template looks like this:

<div id="clientListOutput">

    <li><span data-bind="text: name"></span>
        <div data-bind="template: {foreach: clientAddress}">
            <span data-bind="text: city"></span>
            <span data-bind="text: state"></span>
        </div>
        <hr />
        <ul data-bind="template: {foreach: projects}">
            <li>
                <span data-bind="text: name"></span>
                <span data-bind="text: summary"></span>
                <span data-bind="text: description"></span>
            </li>
        </ul>
    </li>

I don't know if this matters, but you have commas at the end of lines 6-8 on the first snippet. — John
– John, Commented Oct 31, 2012 at 3:36

John · Accepted Answer · 2012-10-31 14:32:11Z

1

I am quite certian you have a typo in your HTML. Here is a working example using ko.observablearray

HTML:

<form data-bind="submit: addItem">
    prop1: <input data-bind='value: prop1, valueUpdate: "afterkeydown"' />
    prop2: <input data-bind='value: prop2, valueUpdate: "afterkeydown"' />
    <button type="submit">Add</button>
    <p>Your items:</p>
    <div data-bind="foreach: items">
        <span data-bind="text: prop1"></span> &nbsp - &nbsp
        <span data-bind="text: prop2"></span>
        <br />
    </div>
</form>

JS:

var SimpleListModel = function() {
    this.items = ko.observableArray();
    this.prop1 = ko.observable("");
    this.prop2 = ko.observable("");
    this.addItem = function() {
        this.items.push({prop1:this.prop1, prop2: this.prop2});
    }.bind(this);  // Ensure that "this" is always this view model
};

ko.applyBindings(new SimpleListModel());

http://jsfiddle.net/NjSBg/2/

I suppose it's also possible you forgot to apply the bindings...

Edit

I appologize for posting the wrong fiddle, right one up now.

self.addClient = function () {
    var client = {
        UserId: self.userId(),
        Name: self.name(),
        Logo: self.logo()
    }
    lucidServer.addClient(ko.toJSON(client));
    self.clients.push(client);
}.bind(self);

You add the parenthesis to get the current static value of the observable

edited Oct 31, 2012 at 14:32

answered Oct 31, 2012 at 4:09

John

13.8k7 gold badges53 silver badges104 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

ledgeJumper Over a year ago

Thanks for the answer, but I still don't see what I am doing wrong. I add the html to the questions, maybe you can catch an error I am not seeing?

ledgeJumper Over a year ago

shit that might be the trick, can't test til this evening.. Makes sense though because a blank record was added to the list, so with the parens perhaps it will bring in the actual value.

ledgeJumper Over a year ago

Ah, I was so hopeful, but nope, still not working. Any idea what could be causing this?? I posted an update to my question with the edits you suggested.

John Over a year ago

@davidisawesome did you also get rid of the extra comma in the client object <s>and change the addClient function so that you are not pushing a json string to the self.clients array</s>?

John Over a year ago

@davidisawesome, I'd recommend you go through some tutorials... anyways here is a working version of the code you gave me, jsfiddle.net/2EX8R/2. On further review there are quite a few things wrong with the code you posted... One of the main things is that you are referencing variables in your template that are not in your client object.

|

Collectives™ on Stack Overflow

knockout observable array not updating after ajax addition

1 Answer 1

6 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

6 Comments

Your Answer

Sign up or log in

Post as a guest

Related